niansa-misc/linux
1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
Code Issues Projects Releases Packages Wiki Activity
linux/drivers/net/can/c_can/c_can.h
Vincent Mailhol cc4b08c31b can: do not increase tx_bytes statistics for RTR frames 
The actual payload length of the CAN Remote Transmission Request (RTR)
frames is always 0, i.e. no payload is transmitted on the wire.
However, those RTR frames still use the DLC to indicate the length of
the requested frame.

As such, net_device_stats::tx_bytes should not be increased when
sending RTR frames.

The function can_get_echo_skb() already returns the correct length,
even for RTR frames (c.f. [1]). However, for historical reasons, the
drivers do not use can_get_echo_skb()'s return value and instead, most
of them store a temporary length (or dlc) in some local structure or
array. Using the return value of can_get_echo_skb() solves the
issue. After doing this, such length/dlc fields become unused and so
this patch does the adequate cleaning when needed.

This patch fixes all the CAN drivers.

Finally, can_get_echo_skb() is decorated with the __must_check
attribute in order to force future drivers to correctly use its return
value (else the compiler would emit a warning).

[1] commit ed3320cec2 ("can: dev: __can_get_echo_skb():
fix real payload length return value for RTR frames")

Link: https://lore.kernel.org/all/20211207121531.42941-6-mailhol.vincent@wanadoo.fr
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: Yasushi SHOJI <yashi@spacecubics.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Tested-by: Jimmy Assarsson <extja@kvaser.com> # kvaser
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
Tested-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
[mkl: add conversion for grcan]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2022-01-05 12:09:05 +01:00

243 lines
6.5 KiB
C
Raw Blame History

/*
* CAN bus driver for Bosch C_CAN controller
*
* Copyright (C) 2010 ST Microelectronics
* Bhupesh Sharma <bhupesh.sharma@st.com>
*
* Borrowed heavily from the C_CAN driver originally written by:
* Copyright (C) 2007
* - Sascha Hauer, Marc Kleine-Budde, Pengutronix <s.hauer@pengutronix.de>
* - Simon Kallweit, intefo AG <simon.kallweit@intefo.ch>
*
* Bosch C_CAN controller is compliant to CAN protocol version 2.0 part A and B.
* Bosch C_CAN user manual can be obtained from:
* http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/
* users_manual_c_can.pdf
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#ifndef C_CAN_H
#define C_CAN_H
enum reg {
C_CAN_CTRL_REG = 0,
C_CAN_CTRL_EX_REG,
C_CAN_STS_REG,
C_CAN_ERR_CNT_REG,
C_CAN_BTR_REG,
C_CAN_INT_REG,
C_CAN_TEST_REG,
C_CAN_BRPEXT_REG,
C_CAN_IF1_COMREQ_REG,
C_CAN_IF1_COMMSK_REG,
C_CAN_IF1_MASK1_REG,
C_CAN_IF1_MASK2_REG,
C_CAN_IF1_ARB1_REG,
C_CAN_IF1_ARB2_REG,
C_CAN_IF1_MSGCTRL_REG,
C_CAN_IF1_DATA1_REG,
C_CAN_IF1_DATA2_REG,
C_CAN_IF1_DATA3_REG,
C_CAN_IF1_DATA4_REG,
C_CAN_IF2_COMREQ_REG,
C_CAN_IF2_COMMSK_REG,
C_CAN_IF2_MASK1_REG,
C_CAN_IF2_MASK2_REG,
C_CAN_IF2_ARB1_REG,
C_CAN_IF2_ARB2_REG,
C_CAN_IF2_MSGCTRL_REG,
C_CAN_IF2_DATA1_REG,
C_CAN_IF2_DATA2_REG,
C_CAN_IF2_DATA3_REG,
C_CAN_IF2_DATA4_REG,
C_CAN_TXRQST1_REG,
C_CAN_TXRQST2_REG,
C_CAN_NEWDAT1_REG,
C_CAN_NEWDAT2_REG,
C_CAN_INTPND1_REG,
C_CAN_INTPND2_REG,
C_CAN_INTPND3_REG,
C_CAN_MSGVAL1_REG,
C_CAN_MSGVAL2_REG,
C_CAN_FUNCTION_REG,
};
static const u16 __maybe_unused reg_map_c_can[] = {
[C_CAN_CTRL_REG] = 0x00,
[C_CAN_STS_REG] = 0x02,
[C_CAN_ERR_CNT_REG] = 0x04,
[C_CAN_BTR_REG] = 0x06,
[C_CAN_INT_REG] = 0x08,
[C_CAN_TEST_REG] = 0x0A,
[C_CAN_BRPEXT_REG] = 0x0C,
[C_CAN_IF1_COMREQ_REG] = 0x10,
[C_CAN_IF1_COMMSK_REG] = 0x12,
[C_CAN_IF1_MASK1_REG] = 0x14,
[C_CAN_IF1_MASK2_REG] = 0x16,
[C_CAN_IF1_ARB1_REG] = 0x18,
[C_CAN_IF1_ARB2_REG] = 0x1A,
[C_CAN_IF1_MSGCTRL_REG] = 0x1C,
[C_CAN_IF1_DATA1_REG] = 0x1E,
[C_CAN_IF1_DATA2_REG] = 0x20,
[C_CAN_IF1_DATA3_REG] = 0x22,
[C_CAN_IF1_DATA4_REG] = 0x24,
[C_CAN_IF2_COMREQ_REG] = 0x40,
[C_CAN_IF2_COMMSK_REG] = 0x42,
[C_CAN_IF2_MASK1_REG] = 0x44,
[C_CAN_IF2_MASK2_REG] = 0x46,
[C_CAN_IF2_ARB1_REG] = 0x48,
[C_CAN_IF2_ARB2_REG] = 0x4A,
[C_CAN_IF2_MSGCTRL_REG] = 0x4C,
[C_CAN_IF2_DATA1_REG] = 0x4E,
[C_CAN_IF2_DATA2_REG] = 0x50,
[C_CAN_IF2_DATA3_REG] = 0x52,
[C_CAN_IF2_DATA4_REG] = 0x54,
[C_CAN_TXRQST1_REG] = 0x80,
[C_CAN_TXRQST2_REG] = 0x82,
[C_CAN_NEWDAT1_REG] = 0x90,
[C_CAN_NEWDAT2_REG] = 0x92,
[C_CAN_INTPND1_REG] = 0xA0,
[C_CAN_INTPND2_REG] = 0xA2,
[C_CAN_MSGVAL1_REG] = 0xB0,
[C_CAN_MSGVAL2_REG] = 0xB2,
};
static const u16 __maybe_unused reg_map_d_can[] = {
[C_CAN_CTRL_REG] = 0x00,
[C_CAN_CTRL_EX_REG] = 0x02,
[C_CAN_STS_REG] = 0x04,
[C_CAN_ERR_CNT_REG] = 0x08,
[C_CAN_BTR_REG] = 0x0C,
[C_CAN_BRPEXT_REG] = 0x0E,
[C_CAN_INT_REG] = 0x10,
[C_CAN_TEST_REG] = 0x14,
[C_CAN_FUNCTION_REG] = 0x18,
[C_CAN_TXRQST1_REG] = 0x88,
[C_CAN_TXRQST2_REG] = 0x8A,
[C_CAN_NEWDAT1_REG] = 0x9C,
[C_CAN_NEWDAT2_REG] = 0x9E,
[C_CAN_INTPND1_REG] = 0xB0,
[C_CAN_INTPND2_REG] = 0xB2,
[C_CAN_INTPND3_REG] = 0xB4,
[C_CAN_MSGVAL1_REG] = 0xC4,
[C_CAN_MSGVAL2_REG] = 0xC6,
[C_CAN_IF1_COMREQ_REG] = 0x100,
[C_CAN_IF1_COMMSK_REG] = 0x102,
[C_CAN_IF1_MASK1_REG] = 0x104,
[C_CAN_IF1_MASK2_REG] = 0x106,
[C_CAN_IF1_ARB1_REG] = 0x108,
[C_CAN_IF1_ARB2_REG] = 0x10A,
[C_CAN_IF1_MSGCTRL_REG] = 0x10C,
[C_CAN_IF1_DATA1_REG] = 0x110,
[C_CAN_IF1_DATA2_REG] = 0x112,
[C_CAN_IF1_DATA3_REG] = 0x114,
[C_CAN_IF1_DATA4_REG] = 0x116,
[C_CAN_IF2_COMREQ_REG] = 0x120,
[C_CAN_IF2_COMMSK_REG] = 0x122,
[C_CAN_IF2_MASK1_REG] = 0x124,
[C_CAN_IF2_MASK2_REG] = 0x126,
[C_CAN_IF2_ARB1_REG] = 0x128,
[C_CAN_IF2_ARB2_REG] = 0x12A,
[C_CAN_IF2_MSGCTRL_REG] = 0x12C,
[C_CAN_IF2_DATA1_REG] = 0x130,
[C_CAN_IF2_DATA2_REG] = 0x132,
[C_CAN_IF2_DATA3_REG] = 0x134,
[C_CAN_IF2_DATA4_REG] = 0x136,
};
enum c_can_dev_id {
BOSCH_C_CAN,
BOSCH_D_CAN,
};
struct raminit_bits {
u8 start;
u8 done;
};
struct c_can_driver_data {
enum c_can_dev_id id;
unsigned int msg_obj_num;
/* RAMINIT register description. Optional. */
const struct raminit_bits *raminit_bits; /* Array of START/DONE bit positions */
u8 raminit_num; /* Number of CAN instances on the SoC */
bool raminit_pulse; /* If set, sets and clears START bit (pulse) */
};
/* Out of band RAMINIT register access via syscon regmap */
struct c_can_raminit {
struct regmap *syscon; /* for raminit ctrl. reg. access */
unsigned int reg; /* register index within syscon */
struct raminit_bits bits;
bool needs_pulse;
};
/* c_can tx ring structure */
struct c_can_tx_ring {
unsigned int head;
unsigned int tail;
unsigned int obj_num;
};
/* c_can private data structure */
struct c_can_priv {
struct can_priv can; /* must be the first member */
struct napi_struct napi;
struct net_device *dev;
struct device *device;
unsigned int msg_obj_num;
unsigned int msg_obj_rx_num;
unsigned int msg_obj_tx_num;
unsigned int msg_obj_rx_first;
unsigned int msg_obj_rx_last;
unsigned int msg_obj_tx_first;
unsigned int msg_obj_tx_last;
u32 msg_obj_rx_mask;
atomic_t sie_pending;
unsigned long tx_dir;
int last_status;
struct c_can_tx_ring tx;
u16 (*read_reg)(const struct c_can_priv *priv, enum reg index);
void (*write_reg)(const struct c_can_priv *priv, enum reg index, u16 val);
u32 (*read_reg32)(const struct c_can_priv *priv, enum reg index);
void (*write_reg32)(const struct c_can_priv *priv, enum reg index, u32 val);
void __iomem *base;
const u16 *regs;
enum c_can_dev_id type;
struct c_can_raminit raminit_sys; /* RAMINIT via syscon regmap */
void (*raminit)(const struct c_can_priv *priv, bool enable);
u32 comm_rcv_high;
};
struct net_device *alloc_c_can_dev(int msg_obj_num);
void free_c_can_dev(struct net_device *dev);
int register_c_can_dev(struct net_device *dev);
void unregister_c_can_dev(struct net_device *dev);
#ifdef CONFIG_PM
int c_can_power_up(struct net_device *dev);
int c_can_power_down(struct net_device *dev);
#endif
void c_can_set_ethtool_ops(struct net_device *dev);
static inline u8 c_can_get_tx_head(const struct c_can_tx_ring *ring)
{
return ring->head & (ring->obj_num - 1);
}
static inline u8 c_can_get_tx_tail(const struct c_can_tx_ring *ring)
{
return ring->tail & (ring->obj_num - 1);
}
static inline u8 c_can_get_tx_free(const struct c_can_tx_ring *ring)
{
return ring->obj_num - (ring->head - ring->tail);
}
#endif /* C_CAN_H */
Reference in a new issue View git blame Copy permalink